When Hillary Clinton announced Virginia Sen. Tim Kaine as her running mate Friday evening, she made a characteristically cautious but responsible choice — indicating that in her pick she was more concerned with finding a long-term governing partner than an electrifying campaigner on the road.

In Kaine — a politician who has never lost a race, whose name has topped Clinton’s list of potential running mates since the process began in earnest back in April — the former secretary of state picked a partner who is similarly heavy on experience and light on dynamic political charisma.

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The hope, Democrats said, is that the Clinton-Kaine ticket will underscore to voters the value of a steady, dependable hand, at home and abroad, when contrasted against the inconsistent and mercurial Donald Trump.

“If you believe that the first and most important consideration is, can this person step into the big job — there's no question that Tim Kaine can,” said Mo Elleithee, director of the Georgetown Institute of Politics, who has worked for both Clinton and Kaine in the past. "He will be an excellent partner in governing."

In recent weeks, Clinton allies have downplayed the political significance of the VP pick, arguing that in a race where the top of the ticket is dominated by figures as big and polarizing as Clinton and Trump, the no. 2 would not move the dial. That sense was bolstered by Trump’s selection last week of Indiana Gov. Mike Pence, who could barely get a word in edgewise at his own announcement press conference.

After an extensive, months-long process during which the campaign considered a host of different options — even vetting a heavyweight candidate from outside the political arena, retired Admiral James Stavridis — the squeaky-clean Virginia senator whose biggest liability is that he is boring, ultimately appealed to Clinton’s cautious nature, as well as her respect for workhorse officeholders cut from her own mold.

“It needs to be someone who whenever they walk into the room you’re glad to see them and you want to have them as part of any conversation,” was the advice from Clinton’s campaign chairman John Podesta, who officially began the vice presidential vetting process after Clinton’s dominated in the New York primary last April. Clinton allies said she was still deliberating over the decision until the last minute, but Clinton appeared to know in her gut who she would eventually pick: Kaine was the only candidate of a list that started at more than two dozen who was invited back for a second private meeting with Clinton, according to a campaign official.

Kaine had also been urged by two men familiar with the demands of the job: President Barack Obama and former President Bill Clinton, those close to the process say.

After Donald Trump’s somewhat more polished performance Thursday night in his speech accepting the Republican nomination, even Democrats who had been pushing for a flashier choice like Massachusetts Sen. Elizabeth Warren or New Jersey Sen. Cory Booker were sobered by what they saw as a challenging four months ahead. “After last night, she needs to make the safest choice possible,” said a former senior White House aide.

“Safe” seems to be Kaine’s middle name. The Spanish-speaking former missionary and onetime swing-state governor sits on both the Armed Services and Foreign Relations committees in the Senate. While the Warren-Sanders wing of the Democratic Party may object to some of his positions on trade and Wall Street regulation, Kaine rarely takes controversial stands or makes painful gaffes, thus fulfilling the Hippocratic oath for vice presidential nominees: First, do no harm.

When he has stuck his neck out, it's been to do battle with the National Rifle Association, whose headquarters are in his state. Kaine, who was governor during the Virginia Tech massacre in 2007, famously called the powerful lobbying group a “paper tiger" and has bragged that despite the millions they spent to defeat him and their assignment of an "F" grade to his record on guns, he's never lost a race in Virginia. Fighting for more restrictive gun laws has also become a core piece of Clinton's primary and general election campaign.

Like Clinton, Kaine is also the son of a small business owner — his father owned an iron workshop and he grew up working as a welder on the shop floor outside of Kansas City.

“He can connect with the working class guys,” said Elleithee, a former senior staffer whose wedding Kaine officiated. “He was Jesuit-educated, which instilled in him that sense of social justice.”

After law school, Kaine became a civil rights attorney, fighting fair housing cases in Virginia, and his was one of the few white families that joined a predominately black Catholic church.Kaine, for all the buzz about his chances and his made-for-VP bio, has been deeply self-effacing during the awkward public tryout process. When asked during a “Meet the Press” interview last month if he was ready to be president, he said no.

"Nobody should ever say they’re ready for that responsibility, because it is so, so huge,” he said, in what some saw as a tacit rebuke of Warren, who answered confidently that she is ready to be commander in chief when asked the same question by Rachel Maddow.

But Kaine's humble, vanilla persona endeared him to Clinton. “I love that about him,” she told CBS News’ Charlie Rose in an interview earlier this week when grilled about whether he was too boring. Added Virginia Gov. Terry McAuliffe, a close confidant of the Clintons who has been pushing for his home-state senator: “If anything, he’s only helped himself through this entire process.”

In addition to McAuliffe, President Obama and Bill Clinton have also privately or publicly expressed their support for Kaine, who was passed over for the No. 2 slot in 2008.

Earlier this week, White House press secretary Josh Earnest, unprovoked, told reporters that Kaine was someone Obama believes would be a good pick for Clinton. “Senator Kaine was one of the first public officials to announce a public endorsement of Senator Obama,” he said. “Senator Kaine served as the chair of the DNC during President Obama’s first year in office, and Senator Kaine is somebody that the president deeply respects.”

Bill Clinton, who has been deeply involved in the process, had also been pushing for two people, but ultimately “Tim is his first choice,” said a source close to the former president. “The advice he gives is much more: Here are the issues you’re going to have; here’s why you need this person. It’s more from experience.”

“Hillary Clinton would feel very compatible working with someone like Tim Kaine,” McAuliffe told POLITICO in a recent interview. “He’s a very thoughtful, quiet negotiator — he doesn’t really care about the limelight. She’s worked with folks like Tim for years. He’s in it for the right reasons — he didn’t jump at the chance to run for the United States Senate. He was perfectly happy to go be a university professor. He doesn’t have to do this for the big rah rah — he can really help people. It’s unique for a lot of folks.”

The prospect that McAuliffe would fill Kaine’s Senate seat also boosted his chances over another appealing choice to the progressive wing of the party, Ohio Sen. Sherrod Brown, whose seat would be filled by an appointee of Republican Gov. John Kasich. Many Clinton allies said they believed Brown would have ultimately been a stronger pick, for his ability to push a progressive message and help win the battleground state of Ohio. But Kaine was still seen as a solid, meat-and-potatoes choice.

McAuliffe said that Clinton likes Kaine’s “worker bee, gets things done” style. “He brings people in. He doesn’t say, ‘This way or the highway’ — he tries to structure compromise,” he said.

Clinton kept her vetting process tight among top aides including longtime attorney Cheryl Mills and campaign chairman John Podesta; in contrast to Trump’s announcement, which leaked out a day early and which his campaign then tried to walk back, the Clinton campaign managed to keep its promise to supporters -- that they would be the first to learn of her pick when alerted via text.

Earlier this week, South Carolina Rep. Jim Clyburn said he had been consulted by the Clinton campaign to discuss Kaine, as well as Labor Secretary Tom Perez and Agriculture Secretary Tom Vilsack. “I’ve had more experience with Tim Kaine than all the three,” Clyburn told reporters. “The three finalists who I understand are the three finalists ... I admire a whole lot.”

As the veepstakes wound to a close on Friday, Kaine kept his cool. Rep. Gerry Connolly (D-Va.) said he bumped into Kaine at a “small, intimate dinner party” on Thursday night and that he was mum about the process. “He seemed quite normal and enjoyed himself and was relaxed and had not heard anything,” Connolly said in an interview Friday morning.

But it's been a period of great expectations for Kaine. After his joint rally with Clinton earlier this month, Clinton invited her potential running mate back to her house and met with him one-on-one for 90 minutes.

Kaine’s biggest liability — aside from his personal opposition to abortion, which has rankled some abortion rights advocates — may be his middle-of-the-road stances on trade deals and financial regulations that put him at odds with the ascendant left wing of the Democratic Party.

"Every progressive I talk to is concerned both about Kaine’s history of trade cheerleading and that this portends Clinton is going to surround herself generally with cautious centrists who don't like ruffling feathers with big corporations," said a progressive Capitol Hill Democrat. “The economic anger that exists somehow still hasn't affected her decisions, which is scary, depressing, and provocative.”

On Friday night, Clinton called other short-listers to inform them that she had made up her mind, including: Agriculture Secretary Tom Vilsack, Labor Secretary Tom Perez, Massachusetts Sen. Elizabeth Warren and former Admiral James Stavridis, who had emerged late in the game as a potential dark horse.

Kaine's selection was greeted with this text message from Trump to his supporters: "Tim Kaine is Hillary's VP pick. The ultimate insiders - Obama, Hillary, and Kaine. Don't let Obama have a 3rd Term."